Internal combustion engine



C. B. MERRY- INTERNAL COMBUSTION ENGINE March 26, 1940.

Filed Oct. 15, 1938 3noentor Clayton B Mary aum Patented Mar. 26, 1 25194 353 v REISSUED UNITED STATES PATENT v OFFICE INTERNAL COMBUSTION ENGINE Clayton B. Merry, Seattle, Wash, assignor of onethird 1 to George B. Merz and one-third to Frank J. Merz, In, both of Seattle, Wash.

5. ed on a carrier cage that is reciprocatedby the opening I1 and connecting-rod IS. The top of 5 connecting rod, and whereby the piston and its this cylinder is closed by a spark plug I9 threaded carrier cage serve as a valve to control and reguthereinto. A series of evenly spaced exhaust .late the entry of fuel into the engine and its ports or'holes 20 is distributed around the cylincombustion chamber. der intermediate of its ends. A hollow piston 2 I- 10' This arrangement materially simplifies the v is slidably and revolubly mounted within the 10 construction of the engine by the elimination of cylinder IS. The top of said piston is provided by-pass and valve parts, makes the engine enwith a concentric opening that is deflned by an tirely concentric and symmetrical whereby equal upwardly projecting flange 22.

1 expansion and contraction takes place in all di- The piston 2| is slidably and revolubly mountl5 rections, increases its efliciency by providing 2. ed on a hollow carrier cage 23. This carrier cage more direct fuel flow, and causes both the wear fits snugly into the piston and terminates short of the piston and cylinder to be uniform by reaof its top and bottom ends. Itsdownward slidson of the revoluble mounting of the piston'on. able movement is limitedby a retainer ring' 24 the carrier cage. that is set into a groove around the lower inner In the drawing: 7 edge portion of the piston as most clearly shown Figure 1 is a view in central, longitudinal verin Fig. 3 of the drawing. The top of the carrier tical section of the engine, with parts shown in cage is preferably, though not necessarily, proelevatiom' vided with a conical protuberance 25. This pro- Fig. 2 is a view in central transverse vertuberance projects into theflanged opening 22 tical section of the same; of the piston 2|. and itsimpingement against 5. Fig. 3 is an enlarged detail view in central thebottom of said opening limits the upward vertical section of the piston and its carrier slldable movement of the carrier cage 23 with e; respect to the piston 2|, thus providing an-annu- Fig. 4 is a view in horizontal section taken on lar Chamber 26 between the tops of said carrier 30- a broken line 44 of Fig. 1; and cage and piston. It also serves as a closure for 30 Fig. 5 is a corresponding view taken on a theflow of tuel as more fully hereinafter set broken line 5--5 of Fig. 1'. forth. A series of evenly spaced holes-21 extend Referring in detail to the drawing wherein through the top of the carriercage around and like reference numerals indicate like parts in the close to th ba e of the conical protuberance 1501' several views, the numeral 5 designates the base- Passage f t The up end of the 35 of the engine which is provided with a crank nectlnz rod I8 extends into a is-n v y case compartment 6. A head 1 is threaded into I neeted t0 the pp P n of the Carrie! 8 one end of this compartment and is prpvided by a W t Din ll W o ends are lolllnaled into with a conduit 8. A fuel tank 9 is connectedto the wall thereof.

40 said conduit and a needle valve l0 in cooper- This engine is of the two cycle type wherein 40 ative arrangement therewith serves as a carh intake, p s firing and au t burettor for the fuel supply. Entry of the fuel is carried out during the upward and downward into the crank case is controlled by a flap valve strokes of the piston. Exhaustion is completed at H which restricts the conduit 8. the limit oflthe downward stroke as shown in A propeller I2 is rotated by a shaft H which. Fig. 1, and firing tak p a at the limit of the 45 is joumaled through the other end wall of the upward Stroke as Shown in In other crank case 6 and engine base 5, and in alignwords, the downward stroke combines both the .ment .with the conduit 8. A disc crank I4 is power and exhaust strokes, and the upward fixed to the'inner end of said shaft and rotates flk om ines both the intake and coml le within said crank case and against said end'wall. sion strokes. 'At the limit of the downward 50 A crank pin I5 is eccentrically fixed to said disc stroke the top of the pistonjust clears the botcrank, and the lower end of-a connecting rod l6 tom edges of the exhaust ports or .holes 20, and is journaled to said crank pin. This connecting at the limit of the upward'stroke the bottom rod extends upward through'an' opening I! in portion of said piston completely covers-said My invention relates to internal combustion engines, and the primary objects of the invention are to provide an engine consisting of a pis-. ton which is both slidably and revolubly mountthe top of the crank case and said openingiis elongated, as shown in Fig'r4, to allow for reciprocative swing of the connecting rod.

A cylinder l8' has its lower end threaded into the top of the engine base 5 concentric with the In the operation of the engine, referring partlcularly to Fig. 1 and assuming that the piston 2| has started on the upward stroke, fuel is sucked in through the conduit 8 and flap valve II and passes upward through the crank case B and opening l1, filling the hollow carrier cage 23, and some of it passing upward through. the

,holes 21 in the top of the carrier cage, and fillsure of the preceding fuel charge in the combustion portion of the cylinder, or by the compressed -air therein when first starting the engine.

Upon reaching the limit of the upward stroke, as shown in Fig. 2, explosion takes place, and the greater downward force of the expanding gas in the combustion portion of the cylinder against the lesser resistance of the incoming fuel charge keeps the opening 22 still tightly closed on the downward stroke of the piston 23. During this downward stroke the pressure within the com-j bustion chamber rapidly decreases due to the expanding fuel charge. At the same time, the pressure within the fuel intake portion of the cylinder below the piston and also in the crank case 6 rapidly increases due to compression of. the piston and the fact that the iiap valve H is closed. Now, when the top of the piston 23 reaches the exhaust ports 28], the pressure within the upper portion of the cylinder is suddenly released as the'burnt gases pass out through said exhaust ports. At this time, the greater and controlling pressure below the piston and within the small chamber 26 greately retards the downward movement of the piston 2i. This allows the carrier cage 23 to bcmomentarily pulleddown and away from the top wall of the piston by the connecting rod l6 acting through the Wrist pin 28, as most clearly shown in Fig. 3, it being understood that said carrier cage is pulled away from the top of the piston for only a fraction of a second, or while the top of the piston is moving down andup the short distance defined by the height of the exhaust ports. The carrier cage 23 slides down until its bottom nearly reaches the retainer ring 22:3, thus creating a passage between the upper conical protuberance 255 and the flanged opening 22 at the top of the piston. The compressed charge of fuel below then rushes up through the spaced holes 2! of the carrier cage and through the opening 22 into the combustion portion of the cylinder. The-flange of said opening concentrates the upward charge of fuel and keeps it away from the exhaust ports 2i), until the scavenging of the burnt gas above is completed. Almost simultaneously the carrier cage is raised by the upward stroke of the connecting rod it whereby the aforesaid passage is closed and the foregoing described cycle of op eratlonsis'repeated. It will thus be seen that the charge of fuel into the combustion chamber is controlled by the difference or relative varia- 'cal.- There are no by-passes on the side to cause unequal expansion or contraction, the exhaust ports are equally and concentrically disposed around the entire cylinder, and there are no delicate valve parts to get out of order. Furthermore, the concentric symmetrical construction herein described, in addition to eliminating unequal expansion, provides 'a direct upward flow of fuel thereby increasing the efllclency oi the engine. Mounting of the piston on the carrier cage so that it is free to revolve in a horizontal direction equalizes both the wear oi the piston and cylin-v der and prevents vertical scoring. The herein described fuel valve, consisting of the piston and carrier cage cooperatively arranged, cannot open until the pressure within the base portion of. the engine is greater than the pressure within its combustion portion, and this occurs during the exhaust period. This engine is primarily intended for use on small or model airplanes, for outhoard motors, and other small uses to which it is adapted, although it is not limited in this respect.

- I claim:

1. A two cycle internal combustion engine con sisting of a cylinder, a piston movable within the cylinder, 2. carrier cage slidably mounted for limited axial movement within the piston, a connecting rod having a wrist pin pivotally connected to the carrier cage, passages through the tops of the piston and carrier cage, exhaust ports intermediate the ends of the cylinder equally disposed around the entire cylinder, and said passages arranged to be closed at all times by impingement of the piston and carrier cage except when the exhaust ports are opened upon movement of the piston.

2. An internal combustion engine consisting of a cylinder, a piston reclprocatlvely movable within the cylinder, 2. carrier cage slidably mounted within the piston for limited axial movement, a connecting rod for reclprocatlvely moving the carrier cage, passages through the tops of the piston and carrier cage arranged to be normally closed by impingement of the one against the other at all times when pressure within the cylinder above the piston is greater than it is below said piston, and a'plurality of exhaust ports arranged to be momentarily opened at the limit of the downward movement of the piston and to reduce the pressure within the cylinder above the piston to a point less than the pressure below said piston whereby the carrier cage is pulled away from the top of the piston by the connecting rod during the exhaust period thus opening the passages through the tops of the piston and carrier cage. 

